How severe is CVE-2026-73373?

CVE-2026-73373 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2026-73373 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (49th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-73373?

CVE-2026-73373 affects Joomla Joomla!. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-73373?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.

When was CVE-2026-73373 published?

CVE-2026-73373 was published on 2026-08-18 and last updated on 2026-09-03.

CVE-2026-73373

CVE-2026-73373 is a critical-severity vulnerability in Joomla Joomla! with a CVSS 3.x base score of 9.8. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-434.

Key facts

Severity: Critical (CVSS 3.x base score 9.8)
CVSS v4: 8.9
EPSS exploit prediction: 1% (49th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-434
Affected product: Joomla Joomla!
Published: 2026-08-18
Last modified: 2026-09-03

Description

Joomla! Core - [20260810] - Unrestricted uploads of SHTML files in Joomla 1.0.0-5.4.7, 6.0.0-6.1.2 - The default list of dangerous files did not include SHTML files. On servers that executed these files, that could lead to code execution.

Frequently asked questions

What is CVE-2026-73373?: Joomla! Core - [20260810] - Unrestricted uploads of SHTML files in Joomla 1.0.0-5.4.7, 6.0.0-6.1.2 - The default list of dangerous files did not include SHTML files. On servers that executed these files, that could lead to code execution.
How severe is CVE-2026-73373?: CVE-2026-73373 has a CVSS 3.x base score of 9.8, rated critical severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2026-73373 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (49th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-73373?: CVE-2026-73373 affects Joomla Joomla!. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-73373?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
When was CVE-2026-73373 published?: CVE-2026-73373 was published on 2026-08-18 and last updated on 2026-09-03.

References

Affected products (1)

cpe:2.3:a:joomla:joomla\!:*:*:*:*:*:*:*:*

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